Fit-for-Purpose Assessment of QuEChERS LC-MS/MS Methods for Environmental Monitoring of Organotin Compounds in the Bottom Sediments of the Odra River Estuary

Organotin compounds (OTCs) are among the most hazardous substances found in the marine environment and can be determined by either the ISO 23161 method based on extraction with non-polar organic solvents and gas chromatography analysis or by the recently developed QuEChERS method coupled to liquid chromatography-mass spectrometry (LC-MS/MS). To date, the QuEChERS LC/MS and ISO 23161 methods have not been compared in terms of their fit-for-purpose and reliability in the determination of OTCs in bottom sediments. In the case of ISO 23161, due to a large number of interferences gas chromatography-mass spectrometry was not suitable for the determination of OTCs contrary to more selective determination by gas chromatography with an atomic emission detector. Moreover, it has been found that the derivatization of OTCs to volatile compounds, which required prior gas chromatography determination, was strongly affected by the sediments’ matrices. As a result, a large amount of reagent was needed for the complete derivatization of the compounds. Contrary to ISO 23161, the QuEChERS LC-MS/MS method did not require the derivatization of OTC and is less prone to interferences. Highly volatile and toxic solvents were not used in the QuEChERS LC-MS/MS method. This makes the method more environmentally friendly according to the principles of green analytical chemistry. QuEChERS LC-MS/MS is suitable for fast and reliable environmental monitoring of OTCs in bottom sediments from the Odra River estuary. However, determination of di- and monobutyltin by the QuEChERS LC-MS/MS method was not possible due to the constraints of the chromatographic system. Hence, further development of this method is needed for monitoring di- and monobutyltin in bottom sediments.     

A New Approach to the Determination of Silicon in Zinc,Lead-Bearing Materials and in Waste Using the ICP-OES Method

This work describes the implementation of the ICP-OES silicon determination method for zinc and lead-bearing materials and waste at the Mining and Metallurgical Works ZGH “Bolesław”. The proposed method was validated. On the basis of linearity tests, it was found that the course of the calibration curve is linear up to a silicon concentration of 100 mg/L, with the determined working range being 0.10–50%. Precision tests, on the basis of which the repeatability was checked, were carried out for nine types of real samples: zinc sulfides, zinc oxides, zinc-lead ore, lead sulfide and zinc-bearing waste. Real samples and six certified reference materials were tested using the ICP-OES radial position. The identified interferences of molybdenum, chromium and vanadium did not statistically significantly affect the measurement results.     

The Influence of High-Intensity Ultrasonication on Properties of Cellulose Produced from the Hop Stems,the Byproduct of the Hop Cones Production

The goal of this work is to evaluate the hop stems, a byproduct of hop cones production, as a potential source of cellulose. Hop stems contain up to 29% of cellulose. The cellulose isolation was conducted through the thermochemical treatment. After high-speed blending, the cellulose was characterized by 67% of crystallinity degree obtained from X-ray diffraction and median diameter of 6.7 nm obtained from atomic force microscopy imaging. The high-intensity ultrasonication (HIUS) was applied to reach further disintegration of cellulose fibers. The longer HIUS treatment resulted in decrease in crystallinity degree even up to 60% and decrease in the fiber diameter up to 4 nm. The Fourier transform infrared spectroscopy (FTIR) spectra showed that HIUS treatment led to changes in intermolecular hydrogen bonds. The stability of cellulose dispersions versus length of HIUS treatment was monitored over 14 days with back dynamic light scattering and laser Doppler electrophoresis methods. Obtained results are evidence that the hop stems are a potential source of cellulose and that it is possible to obtain stable dispersions after HIUS treatment. This was the first time that the properties of hop cellulose have been described so extensively and in detail after the use of HIUS treatment.     

Application of Levan-Rich Digestate Extract in the Production of Safe-to-Use and Functional Natural Body Wash Cosmetics

The study focused on the evaluation of the possibility of using a levan-rich digestate extract in the production of safe and functional body wash cosmetics. Model shower gels were designed and formulated on the basis of raw materials of natural origin. Prepared prototypes contained various extract concentrations (16.7; 33; 50%). A gel without extract was used as a reference. The samples were evaluated for their safety in use and functionality. The results showed that the use of high-concentration levan-rich digestate extract in a shower gel resulted in a significant reduction in the negative impact on the skin. For example, the zein value decreased by over 50% in relation to the preparation without the extract. An over 40% reduction in the emulsifying capacity of hydrophobic substances was also demonstrated, which reduces skin dryness after the washing process. However, the presence of the extract did not significantly affect the parameters related to functionality. Overall, it was indicated that levan-rich digestate extract can be successfully used as a valuable ingredient in natural cleansing cosmetics.     

Selective Preparation of Phosphorus Mononitride (P≡N) from Phosphinoazide and Reversible Oxidation to Phosphinonitrene

The interstellar candidate phosphorus mononitride PN, a metastable species, was generated through high-vacuum flash pyrolysis of (o-phenyldioxyl)phosphinoazide in cryogenic matrices. Although the PN stretching band was not directly detected because of its low infrared intensity and possible overlaps with other strong bands, o-benzoquinone, carbon monoxide, and cyclopentadienone as additional fragmentation products were clearly identified. Moreover, an elusive o-benzoquinone-PN complex formed when (o-phenyldioxyl)phosphinoazide was exposed to UV irradiation at λ=254 nm. Its recombination to (o-phenyldioxyl)-λ⁵-phosphinonitrile was observed upon irradiation with the light at λ=523 nm, which demonstrates for the first time the reactivity of PN towards an organic molecule. Energy profile computations at the B3LYP/def2-TZVP density functional theory level reveal a concerted mechanism. To provide further evidence, UV/Vis spectra of the precursor and the irradiation products were recorded and agree well with time-dependent DFT computations.